Relay mechanism



" May 24, 1938.

FIG.

A. C. MAGRATH RELAY MECHANISM Filed May 14, 1937 2 Sheets-Sheet l /NVEN7'OR AC MAGRA TH m. SE'ORNE y 24, 3 A. c. MAGRATH 2,118,258

RELAY MECHANISM Filed May 14, 1937 2 Sheets-Sheet 2 n lu l hit 45 INVENTOR AC. MAGRATH A TTORNEV Patented May 24, 1938 UNITED STATES PATENT OFFICE RELAY IVIECHANISM Application May 14, 1937, Serial No. 142,631

5 Claims.

This invention relates to improvements in relay mechanisms and particularly to means for locking said mechanisms in actuated position.

It is an object of this invention to provide mechanisms of this kind in which the maintaining thereof in operated position is economically effected both in regard to the saving of holding current and in simplified structures.

Heretofore systems have been provided having locking means for armatures such as arrangements in which a heavy armature, attracted by a substantial current in one winding, is locked in operated position by a lighter armature attracted by a reduced current in another winding after the heavier current through the first winding ceases.

It is a feature of the present invention to provide an improved relay mechanism of this type comprising a single energizing winding and two armatures and in which one armature may be held in actuated position by the other armature with the winding energized by a fraction only of the original operating current.

Another feature is an arrangement whereby the two armatures may be operated simultaneously and one of these, that is, an auxiliary armature operates a stop member or latch which holds the other or main armature. The mechanism is so constructed that no interference will occur when said two armatures are operated simultaneously.

The invention is illustrated in the accompanying drawings in which:

Fig. 1 shows a front view of a cross-bar switch structure with applicants invention applied thereto;

Figs. 2 to 6 show various views of a relay mechanism constructed in accordance with the applicants invention applied specifically to the cross-bar switch structure as disclosed in Fig. 1;

Fig. 2 is a side view of the relay looking from the right side thereof as viewed in Fig. 1;

Fig. 3 is a bottom view;

Fig. 4 is a view similar to Fig. 2 except that the armatures are shown in locked positions;

Fig. 5 is a view similar to Fig. 3 except that the armatures are shown in locked position;

Fig. 6 is an enlarged perspective fragmentary view of the latch mechanism in normal position.

Figs. 7 and 8 are fragmentary views of a modified form of the applicants invention;

Fig. 7 shows a bottom View of the relay structure with the armatures in normal position; and

Fig. 8 is a fragmentary perspective of the parts as illustrated in Fig. 7.

While relay mechanisms in accordance with the applicants invention may be used in a number of different ways and in general may be applied to different types of cross-bar switches, it has been illustrated as applied to a particular type of switch as described in the Patent to J. N. Reynolds 2,021,329 of November 19, 1935.

Referring now to the drawings and particularly to Fig. l, a general description will be made of the essential parts of the cross-bar switch shown to which the applicants invention has been applied. For a full description of the details of this switch and its operation reference may be had to the above-mentioned patent to Reynolds. This switch consists of a frame comprising memhers I, 2, 3, and 4, five horizontal bars 5 and a series of ten vertical bars 6. The first, second and last of the latter bars only have been shown in full with their corresponding horizontal and vertical rows of contact sets. The first horizontal row of contact sets is marked I3 and the first vertical row is marked I4, while the second horizontal row is marked I5. The actuating spring for connecting the horizontal contacts I3 to the vertical contacts I4 is shown at I6 and the actuating spring for connecting the horizontal contacts I5 with the vertical contacts I4 is shown at H. The first or upper horizontal bar 5 may be rotated in one direction to cause the associated selecting fingers 20 to select the upper row of horizontal contacts I3 by the operation of the magnet 2| and be rotated in the opposite direction to select the second row of horizontal contacts I5 by the operation of magnet 22. The selecting finger in the case of the operation of the magnet 2| is placed in front of the actuating spring I6 and on the operation of magnet 22 is placed in front of actuating spring H. The vertical operating bar 6 which is mounted on the member 26 may be actuated by magnet 21 through the armature 28 integral with the operating bar 6 to cause said bar to operate on an actuated selecting finger 20 to press an actuating spring such as I6 or H against the contact set I3 or I5 to make contact with a vertical contact set Id. The members 26 are secured to the upper and lower frame members I and 2 while the horizontal bars 5 are pivotally supported between the frame members 3 and 4. After the magnet 21 has operated on the armature 28 the corresponding bar is locked in operated position in a manner that will be hereinafter described and the operating current in magnet 21 may then be reduced to a small fraction of its original value to hold this bar in actuated position. The corresponding horizontal bar 5 may then be returned to normal and the established connection is maintained until the circuit for the magnet 21 is broken at which time the bar 9 is released and the selecting finger 29 returns to normal causing the connections through the contact sets to be opened.

Referring now specifically to Figs. 2 to 5, the details of the relay mechanism as embodied in this cross-bar structure will be described. The magnet 2'! consists of a winding 39 on a core 3| which is fastened to a U-shaped pole-piece 32. This pole-piece may be welded to the support 26. The vertical bar 6 is mounted with its armature 28 on knife edges on the sides of the U- shaped pole-piece 32 at points 34 and 35 and is prevented from displacement by the spring 39 which is provided with a right angle projection 31 for this purpose. The auxiliary armature 39 is mounted on a knife edge at 49 on a mounting plate ll which is secured to the bottom portion of the U-shaped pole-piece 32 by means of a nut 93 which also secures the core 3! to the pole-piece 32. This armature 39 is prevented from displacement by a spring member 94 mounted between the nut 93 and the plate 4| and is provided with a right angle projection for this purpose. This auxiliary armature 39 is held in released position by spring 17 secured thereto and resting on the bottom of the lower side member of the U- shaped pole-piece 32 by means of a projection 49, as shown in Fig. 3. The main armature 28 when attracted takes its position against the free end 59 of the core 3! and the auxiliary armature when attracted takes the position with its bent and free end against a special magnetic spoolhead 5! attached to the free end 59 of the core 3!. This bent end of the auxiliary armature 39 is bifurcated with one prong 61 bent to engage a cut-in portion on the spoolhead 5| and thus serves to guide the auxiliary armature 39 to prevent it from a sidewise shift when locking the main armature in the manner hereinafter to be described.

On the main armature 28 is mounted a right angle bracket 53 and to this bracket is secured a flexible spring member or latch 54 riveted at 55 and having prongs 59 to prevent it from shifting sidewise. This is clearly shown in Figs. 3 and 6. The end of spring 54 is bent forward so as to present a portion 5'! with its upper surface flush with the lower surface of the bracket 53. This portion 5? is provided with a right angle bent edge portion 59 to provide a wider contact surface, as the spring itself is rather thin. This portion 5? engages normally an extension 69 on the auxiliary armature 39. The bracket 53 is cut to form a right angle hook-shaped member 95 the end of which normally engages the auxiliary armature 39 and serves as a back stop for this armature.

The operation of locking the main armatiu'e 28 will now be described. When the armature 28 is attracted toward the free end 59 of the core 3i, the bracket 53 carries the spring 54 from its normal position under the extension 69 to one side thereof, as shown in Fig. 5 and at the same time the auxiliary armature 39 is attracted so that the free end thereof engages the spool-head 35. This causes the extension 69 on the auxiliary armature 39 topress the spring 54 downward away from the bracket 53 but when both armatures are fully attracted, the portion 5! of the spring 53 wil be placed as shown alongside of the extension 99 with the right angle portion 58 engaging the edge 95 of the extension 69. The auxiliary armature if remaining in this position will therefore now lock the main armature in actuated position. The operating current required for operating these two armatures may now be reduced to a small fraction of its original value and need only be suficient to hold the auxiliary armature 39 against the spool head 5| as the main armature is securely locked in its operated position by the portion 58 of spring 54 energizing edge 65 of the bracket of the auxiliary armature 39. Thus, it will be seen that both armatures can operate simultaneously due to the flexibility of the spring 54, and the position of the spring 54 and extension 69 are such that there is practically no pressure on the armature 39 on the part of the main armature 28 to dislodge the armature 39 from its actuated position. It should be noted that the force exerted by the armature 28 in its attempt to return to normal is directed solely against the edge 65 of the extension 50 and the armature 39 itself is guided by the prong 6! engaging the portion 68 of the spoolhead 5| to prevent a sidewise shift of the armature 39. This force exerted at the point is near the pivotal point of the auxiliary armature 39 while the magnetic force exerted on portion GT is at the extreme free end of the armature. It is readily seen that sidewise pressure of the prong 67 on portion 98 is considerably reduced as compared with the pressure of the bracket 53 at point due to this difference in leverage. Consequently the magnetic force required to hold armature 39 in actuated position need only be sufiicient to overcome the tension of the restoring spring 41 which in turnmust be sufficient to overcome the frictional pressure at point 55 when the magnet is deenergized to return the armature 39 to normal and thus release the armature 28.

Referring now to Figs. 7 and 8, a modified disclosure is shown in which the bracket 53 of the armature 28 is not provided with any spring, but the auxiliary armature 39 is provided with a flexible spring 19 that ends in a right angle extension ll that normally engages the bracket 53 on its upper surface. When the armature 28 is energized, the bracket 53 will slip from under the extension H and as the auxiliary armature is operated, the spring 19 will be pressed against the bracket 53 and consequently when the extension H slips 01f the upper edge of projection 53, it will come to rest on the side of this bracket at point 72. Thus the spring [9 will lock the bracket 53 to hold the armature 28 in operated position in a similar manner to that described in connection with Figs. 2 to 6.

What is claimed is:

1. In a relay mechanism, a single energizing winding, 2. main armature and an auxiliary armature, both armatures operated to actuated positions by certain energizations of said winding and the auxiliary armature held in its actuated position by certain less energizations of said winding, and mechanical means movable on the operation of both armatures for locking the main armature in actuated position under control of the auxiliary armature and for maintaining said main armature locked if the energization of the winding is subsequently reduced to a point sufiicient to hold the auxiliary armature in operated position.

2. In a relay mechanism, a single energizing winding, a heavy armature and a lighter armature both operated simultaneously to actuated positions by a certain encrgi'zation of said winding, and latching means operative on the operation of both armatures for locking the heavier armature in actuated position by the lighter armature and for maintaining said heavier armature locked if the energization of the winding is subsequently reduced to a certain point sufficient to hold the lighter armature in operated position.

3. In a relay mechanism, an energizing winding, a main armature and an auxiliary armature both operated simultaneously to actuated positions by certain energizations of said winding and the auxiliary armature held in its actuated position by certain less energizations of said winding, and a flexible latch member on one of said armatures in position to lock the main armature in operated position, when both armatures are operated in actuated position, and in position to maintain the main armature locked it the energization of the winding is subsequently reduced to a point sufficient to hold the auxiliary armature in operated position.

4. In a relay mechanism, an energizing winding, a main armature and an auxiliary armature, a relatively long projection on the auxiliary armature, and a flexible latch member secured to the free end of the projection on the main armature cooperating with the projection on the auxiliary armature for locking the main armature in actuated position when both armatures are operated by the energization of the winding and for maintaining it locked when the energization of the winding is reduced to a point sufficient to hold the auxiliary armature in operated position. 5. In a relay mechanism a single energizing winding, a main armature and an auxiliary armature, both armatures operated to actuated positions by a certain energization of said winding, a latching member on each of said armatures cooperating on the operation of said armatures for locking the main armature in operated position when both armatures are operated and cooperating to maintain the main armature locked if the energization of the winding is subsequently reduced to a point where it will only hold the auxiliary armature in operated position.

ARTHUR C. MAGRATH. 

